I think the answer lies somewhere in your question. "You never used it" so you end up forgetting it. You just need to practice everyday. There are several books you could read to begin with and know the fundamentals of JavaScript, e.g 1) JavaScript: The good parts 2) JavaScript Ninja etc. Also websites such as codewars.com offers a bunch of programming task to get you hands a little dirty (you can try to solve one task daily).